<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>基本选择器</title>
    <style>
        div{
            color: palevioletred;
        }

        .cls{
            color: aqua;
        }


        #dev1{
            color: cornflowerblue;
        }
        #dev2{
            color: cadetblue;
        }
    </style>
</head>
<body>
    <div>div</div>
    <div class="cls">div</div>
    <div class="cls">div</div>

    <div id="dev1">div</div>
    <div id="dev2">div</div>
</body>
</html>